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<script>

// 逗号运算符 ,
// 1.使用逗号运算符可以在一条语句中执行多个操作
// var a = 1;
// var b = 2;
// var c = 3;
// var a = 1, b = 2, c = 3;
var a = 1,
    b = 2, 
    c = 3;
// 2.返回一个整体的最后一个值

console.log( a );
console.log( b );
console.log( c );
console.log( a,b,c );// 1 2 3
console.log( (a,b,c) );// 3


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